The present invention relates to a system and method for detecting hazardous materials inside containers and, more particularly, to a system and method for detecting hazardous materials inside shipping containers, such as semi-trailers cargo boxes, shipping containers, rail cars and the like, in which mail, merchandise, and goods are shipped.
All economies depend upon the physical shipment of materials for their functioning including the shipment of mail, merchandise, raw materials, and other goods. Typically, the materials are shipped in some type of shipping containment or cargo box. Such containments or boxes include semi-trailers, large trucks, and rail cars as well as inter-modal containers that are carried on container ships, off-loaded and carried by specially designed rail cars, and thereafter transferred to tractor-trailers for delivery to their final destination.
In some circumstances, it is desirable to subject the cargo to some type of inspection to determine the presence of hazardous or impermissible materials, including biological and chemical materials. In general, sophisticated sensing systems are known for the detection of hazardous biological and chemical materials. For example, such systems can include conventional laboratory facilities as well as mobile or semi-mobile units that can automatically or semi-automatically detect the presence of the undesired substance or substances. One such vehicle-mobile system is the Joint Biological Point Detection System (JBPDS) developed for the United States military and designed to detect the presence of a number of biological pathogens. Others include sensor or detectors for hazardous chemicals, explosives, illicit drugs, radioactive particles, and other hazardous materials. These sensors can be used single, or in combinations, to detect as many types of hazardous particles or vapors as required.
Currently when there is suspicious mail, it is all bulk irradiated as was done during the recent anthrax problem thereby delaying some mail for months and damaging or destroying some of the mail due to problems caused by the irradiation. For example some of this irradiated mail became brittle and pieces broke off.
U.S. Published Application No. US 2002/0126008 published Sep. 12, 2002 and filed Oct. 31, 2001 discloses use of sensors at various locations within a typical mail processing system to sense the presence of a harmful agent. This system is completely open to the ambient atmosphere. (The present application is based upon a provisional patent application filed Oct. 26, 2001.)
U.S. Published Application No. US 2002/0124664 published Sep. 12, 2002 and filed Feb. 1, 2002 discloses use of a mail sampling system used in a room separate from the remainder of a post office facility and in which there is an air intake fan and all outgoing air is filtered before release. Most often openings are formed in the parcels and mail for the sampling. The sampling system is said to determine whether mail is contaminated with a chemical or biological agent. (The present application is based upon a provisional patent application filed Oct. 26, 2001.)
U.S. Pat. Nos. 5,942,699 and 6,324,927 disclose a manner of collective sampling of cargo items for contaminants such as chemical residues. The cargo items are placed into a special airtight chamber and physically agitated, such as by vibration, to release particulates and vapors from the items, and bursts of high pressure air is sent into the chamber. Heated air may also be used.
U.S. Pat. No. 3,915,339 discloses use of pressurized air into a container to loosen and cause free flow of material therein move.
U.S. Pat. No. 3,998,101 discloses a method and apparatus for sampling the atmosphere in non-hermetically-sealed containers by enclosing baggage in a chamber and varying the air pressure cyclically to mix a portion of the air in the baggage with the air in the chamber and a vapor detector is used to detect the presence of explosives or drugs in the baggage.
U.S. Pat. No. 4,580,440 discloses a method of detecting a contraband substance in freight cargo in which the container is agitated to disturb particulates therein and samples are taken of the air containing such particulates. The collected particulates are heated to drive off vapors indicative of the contraband substance and the vapors are analyzed in a mass analyzer.
U.S. Pat. No. 4,718,268 discloses a method and apparatus for detecting a contraband substance in freight cargo similar to that of U.S. Pat. No. 4,580,440 mentioned above.
U.S. Pat. No. 4,764,351 discloses a sterilization method and apparatus using a gaseous agent for sterilizing a gas for use in treating materials.
U.S. Pat. No. 5,322,603 discloses a method of an apparatus for treating infections medical wastes is which large sizes of medical waste in a sealed body are exposed to microwaves and heat.
U.S. Pat. No. 5,470,546 discloses apparatus for storing and sterilizing bio-hazardous waste in which air is evacuated and pressurized steam is injected.
U.S. Pat. No. 5,591,117 discloses a method and an apparatus for the disposal of material containing infective microorganisms such as bacteria, fungi and viruses by introducing the material into a container which can be charged with ozone and exposed to the action thereof until the microorganisms are killed, and then the ozone is discharged from the container and converted to a lower valence level and the container is then evacuated.
U.S. Pat. No. 5,700,426 discloses a method for decontaminating or sterilizing xe2x80x9cin situxe2x80x9d a vacuum sealed container and device for implementing such method for sterilizing or decontaminating microorganisms or dangerous products.
U.S. Pat. No. 5,841,038 discloses a remote sampling device for possibly hazardous content of a container. A hollow needle punctures the container and is used to withdraw the contents or to introduce another substance. An inert gas can be introduced into the area where the needle punctures the container.
U.S. Pat. No. 5,859,362 discloses a trace vapor detection method and device of sampling a volume of air suspected of containing drug vapors, removing particulate matter and binding vapors of the drug for further analysis. The device has a sampling, filtration and vacuum port components.
U.S. Pat. No. 6,159,422 discloses methods and apparatus for the treatment of hazardous biological waste materials. A biological waste material is placed into a chamber and a vacuum applied. Water vapor is introduced into the chamber and electromagnetic radiation energy is applied to produce a plasma.
U.S. Pat. No. 6,183,950 discloses a method and apparatus for detecting viruses using primary and secondary biomarkers. There is a sampling section for sampling the atmosphere and includes an intake device for taking a sample. It includes a heater for distilling any cholesterol and/or fatty acids from the sample. There is an analysis section for determining whether cholesterol and/or fatty acids that are indicative of the likely presence of a virus in the sample are present.
U.S. Pat. No. 6,295,860 for explosive detection system and sample collecting device in which luggage enters the device and leaves the device after inspection in which a vapor leaking from the luggage is sampled by a sampling probe, negative corona discharge is used to ionize the vapor, and a mass spectrometer is used to detect the ionized vapor to determine whether or not an explosive is present.
Patent Abstracts of Japan Pub. No. 02159554 A published Dec. 12, 1988, Application No. 63313358 discloses a monitoring method of a pathogen or allergen in which a biosensor is provided near a suction port for air conditioning provided for each room of wall surface which tends to gather mold.
WO 91/09307 published Jun. 27, 1991, for Explosive Detection Screening System detects vapor or particulate emissions from explosives and other controlled substances and reports their presence and may also report the concentration. There is a sampling chamber for collection of vapors or other controlled substances and a concentration and analyzing system, and a control and data processing system for the control of the overall system. There are a number of U.S. patents in this series, including the following: U.S. Pat. Nos. 4,987,767; 5,109,691; 5,345,809; 5,465,607; and 5,585,575.
The U.S. Postal Service has no way of determining if anthrax, or other hazardous materials, are contaminating items of mail. It is desirable to do this before mail enters sorting and distribution centers. A convenient place to do this is in semi-truck trailers (containers) that are loaded with mail from local centers and are trucked to main distribution centers. These containers remain for as much as 24 hours before the mail is removed into the distribution center. This is the time for analysis.
The present invention provides a system and method for detecting hazardous materials inside containers and cargo carriers including semi-trailers, trucks, rail cars, intermodal shipping/cargo containers, and the like.
In one type of system air flow is established within the container to sweep hazardous particles that are entrained in the interior air and dislodge particles from surfaces therein and sweep the particles into a sensor unit for analysis. A shipping container may be provided with at least one wall surface, preferably the floor surface, as an air distribution plenum with air-flow holes or openings therein to allow the establishment of an air flow path within the container. The air flow follows a path upwardly from the floor-located distribution plenum upwardly through the cargo to entrain or otherwise carry or convey particulates, vapors, molecules, or atoms of material upwardly in the container to an exit port or opening. During the time that the air flow pattern is established, a hazardous-materials detection sensor or sensor system is located at or otherwise introduced into the air flow pattern, preferably at or downstream of the air exit port, for a sufficient period of time to sample the flow for a plurality of undesired or hazardous materials.
In another form of the invention, semi-trailers commonly used to ship mail, packages, and other materials are provided with a load-carrying distribution plate that is spaced above the bottom of the trailer body. The distribution plate or surface defines an air distribution plenum therebeneath and includes a plurality of holes distributed across its surface. The air flow pattern can be established by an air-moving fan located within the container or by an auxiliary piece of equipment that connects to the container through an air inlet port and air outlet port to establish a desired air recirculation flow for some period of time. Once the flow has been established, a sensor or sensors are located within the exhaust flow for some period of time sufficient to effect the detection of any undesired or hazardous materials.
The present invention advantageously provides a system and method for quickly and efficiently detecting hazardous materials inside containers typically used to ship materials, including mail, cargo, consumer goods, merchandise, and the like, while the shipped materials are contained and prior to the unloading of the container and possible dissemination/distribution of any hazardous materials.
Other features and advantages will be apparent from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawings.